The present invention relates to apparatus for abrading seed kernels, for example to remove seed hulls and tough outer skin from seeds.
A variety of methods and apparatus have been used in the past for dehulling grain, such as oats, and the like. Most persons who have been around maturing oat in a field have stripped oat grains from the stalks and have rubbed the grains between their hands to dislodge the outer hulls. Examining the grain remaining shows a tough outer skin that must be removed if the inner portion is to be used for human consumption. The oat kernel is only illustrative of many of the grains that are used for human food such as barley, rye, and the like. A simple mechanism is desired for removing both the outer hulls as well as the tough outer skin from the grain kernels. One apparatus used for this purpose in the past is shown in U.S. Pat. No. 128,912. The grain decorticating machine there shown has a plurality of funnel shaped wheels with roughened surfaces. A first set including a plurality of such wheels are mounted for rotation on a drive shaft. A second set of such wheels are mounted to a stationary frame, thereby providing adjacent surfaces which move relative to each other. Grain is passed between the adjacent surfaces and the decorticating takes place therebetween. Various other types of such apparatus are illustrated in U.S. Pat. No. 28,117 (Turner), U.S. Pat. No. 52,774 (Van Peyma), U.S. Pat. No. 126,567 (Newman), U.S. Pat. No. 166,416 (Seck), U.S. Pat. No. 504,173 (Provost), U.S. Pat. No. 668,843 (Smith), U.S. Pat. No. 1,051,877 (GabbettFairfax).
A problem commonly encountered in the past has related to the fact that the hulls and outer skin e.g. pericarp portions of the seeds of various grains differ as to the ease of removal. In some instances, a substantial amount of working is required in order to dislodge the hulls and pericarp portions. In other instances, the hulls and pericarp are very easily removed and, if subjected to substantial working, the heart of the grain is broken up. The present invention overcomes such prior difficulties and provides apparatus which is adjustable to provide lesser or greater amounts of working of the kernels, depending on the tenacity of the hulls and pericarp. Moreover, the present apparatus further provides mechanism for loosening the hull and pericarp prior to the abrading mechanism.